Wolff, K. (1988). Natural selection in Plantago species: A genetical analysis of ecologically relevant morphological variability. Rijksuniversiteit te Groningen.
Chicago-viite (17. p.)Wolff, Kirsten. Natural Selection in Plantago Species: A Genetical Analysis of Ecologically Relevant Morphological Variability. Netherlands: Rijksuniversiteit te Groningen, 1988.
MLA-viite (8. p.)Wolff, Kirsten. Natural Selection in Plantago Species: A Genetical Analysis of Ecologically Relevant Morphological Variability. Rijksuniversiteit te Groningen, 1988.
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